Leaf-spring.



PATENTED JAN; 3, 1905.

2 SHEETS-SHEET 1.

s W BALDWIN LEAF SPRING.

APPLIOATION FILED MAR. 14, 1904.

' PATENTED JAN. 3, 1905.

s. W. BALDWIN.

LEAP SPRING.

APPLICATION FILED MAR.14, 1904.

2 SHEETS-SHEET 24 lilo. 779,021.

NITED STATES Patented January 3, 1905.

PATENT FFICE.

LEAF-SPRING.

SPECIFICATION formingpart of Letters Patent No. 779,021, dated January 3, 1905.

Application filed March 14, 1904. Serial No. 198,081.

To (all whom, it may concern.-

Be it known that I, STEPHEN WV. BALDWIN, a citizen of the United States, residing at New York city, Manhattan borough, in the county of New York and State of New York, have invented certain new and useful Improvements in Leaf-Springs, of which the following is a specification.

This invention relates to and has for an object to provide certain improvements in leafsprings, and more particularly to means for holding the plates or leaves of a spring in their assembled and operative position, and for a further object to provide means to distribute and localize the pressure derived from the instrumentality employed in so holding the spring members or elements and means to render such pressure definite and adequate.

In the drawings accompanying and'forming a part of this specification a form of my invention is illustrated, and in which- Figure 1 is a side view of an'elliptical spring. Fig. 2 is a top view thereof, partly broken away. Fig. 3 is a central cross-section. Fig. 4 is an enlarged detail of a side view, partly broken away. Fig. 5 shows a form of wedgeplate. Fig. 6 shows a band or yoke. Fig. 7

shows a form of wedge, and'Fig. 8 is a detail showing a method of assembling the springplates. I

The spring herein shown for purposes of illustration is such as is frequently employed in heavy work-as, for instance, in railway equipmentand more particularly for locopresent illustration this yoke or band is shown.

rigid, the top and bottom members being securely and rigidly held or bound together by the side members, one desideratum being to present a pair of members upon the top and bottom of the pile which when the clamping takes place will present substantially stationary faces or abutments to the reaction from the spring-leaves and to the reaction from the pressure of the clamping instrumentalities.

The plates or leaves after assemblage will be yoked or held together and clamped by suitable wedges, (designated in a general way by 16,) and a plate (designated in a general way by 17) may be interposed between the top member of the yoke and the face of the outermost leaf of the pile. The plate illustrated for such purpose in Fig. 5 comprises a body portion having a face 18 to rest upon the pile of leaves, or rather upon the contiguous face of the outermost leaf, and a face 19 to engage in the initial assembling with the top portion of the yoke. The plate and yoke, as illustrated in Figs. 5 and 6, respectively, are disassembled one from the other and from the spring, the dotted lines (designated by 20) connecting such parts indicating the direction of assemblage. The plate may be provided with stop-faces 21 to limit its insertion within the yoke and also to prevent its being displaced in the operation of clamping the leaves in the yoke. It will be observed that the plate illustrated in Fig. 5 is thicker at the end 22 than it is at the end 23 and that between such ends there is a plane face 2 L inclined relatively to the faces 18 and 19, which latter face in the present instance is upon the portion 25, which divides or separates the two sides of the plate, making guideways substantially parallel to the general longitudinal line of the spring-leaves when in their assembled position, and that such guideways occupy positions upon the respective sides of the longitudinal median line of the spring-leaves. In assembling the springs when such a plate is employed after it has been placed in position and the leaves have been brought into their assembled position the wedges may be inserted in the guideways and driven tightly therethrough, the faces 21 preventing the plate from moving, and the wedges moving upon the inclined planes 24 will thereby press the spring-leaves together by pressure independently applied upon the respective sides of said longitudinal median line. After the wedge has been sufficiently tightlate in the pile of leaves to constitute any particular spring to such an extent that if a single wedge approximately the width of the spring-leaf were driven between the uppermost leaf and the abutment provided therefor the difference in thickness of one side of the pile relatively to the other side of the pile would cause the Wedge to twist and assume a position inclined to the general line of the spring-leaves, and an efficient clamping consequently would not be had; but by the application of pressure independently to the respective sides of the spring-pile it as a whole is securely clamped together and without such disadvantageous feature. It is considered that this form of securement of spring-leaves not only has the valuable feature of readily and securely clamping the leaves in the assembled pile, but that by evenly distributing the initial tension under which the plates or leaves are held when the spring is in normal condition, or without the application of load, will also maintain the spring in the proper relation as to its elemental parts or plates whereby after having clamped the spring-pile securely together there is less liability of its becoming disarranged, and if it is desired to tighten the spring-pile upon one side of the median line independently of the other, owing to any contingency which may arise in practice, it may readily be done without interfering with the other side thereof.

In the manner in which plates or springs are generally made if the plates are piled loosely one upon the other they will engage at the ends and there will be at the center a slight amount of space and when the springs are in working position there is a certain amount of initial tension throughout the spring. Heretofore it has been customary in springs for railroad use, particularly heavy locomotive-springs, to pile the leaves or plates up in the position they are to occupy, place a band upon the plates, apply pressure to such band, and bring the springs together and upset the sides of the band, the band generally being applied while it is red hot. After the removal of the pressure of the presser the contraction of the cooling of the band will be relied upon to bind the plates together. By this means it is impossible to know exactly the amount of pressure which will be exerted upon the spring when it is ready for use. Hot bands are objectionable in that they tend to draw the temper of the leaves locally, thus producing an ununiform temper throughout each leaf of the spring; but by my invention it is possible toapply a definite and adequate pressure to the leaves without heating the band or yoke, and this definite pressure is continuous throughout the life of the hand, thereby producing a reliable and continuously-operative means for holding the several leaves of a spring together. The yoke or band may be provided with a hole at its top, (designated in a general way by 30,) and the ends of the plate 17 may project when assembled with the band upon each side thereof or project in the general direction of the length of the spring-plates, whereby the plungers (designated in a general way by 31) may engage the plate upon the rib 25 at its ends and center and press the springs into the desired position. A press for operating such plungers may be employed which has upon it an indicator, so that the workman may know how much pressure the springs are held together with and by that means obtain a set of springs which are all uniform as to the initial tension of the springs. After the leaves have been pressed together with the desired amount of pressure the wedge 16 may be inserted and the end turned up. If the end of the wedge does not protrude sufficiently far to be curled up, it may be peened over, or other means may be employed for holding it.

Having thus described my invention, I claim 1. A leaf-spring having the leaves clamped at the central portion by pressure applied by wedges to the respective sides thereof one independently of the other.

2. In a spring the combination with a number of flat leaves piled up one upon the other and means embodying wedges to clamp the same together by pressure independently applied thereto uponthe respective sides of the longitudinal inedian line.

3. A spring embodying anumber of leaves assembled in a pile one upon the other flatwise; a yoke embracing the same and having a portion to receive the flat face of the outermost leaf upon one side of the pile and to receive the reaction in one direction of clamping the leaves together, and independent wedges to press upon the flat face of the outermost leaf upon the other side of the pile adjacent to the respective edges thereof and upon a fixed portion of the yoke common to both.

4. In a spring the combination with a pile of leaves, of a rigid band surrounding the same; I

a plate interposed between the outermost leaf of the pile and the band and having guideways adjacent to the respective edges of the said leaf; and wedges in such guideways to clamp the said pile of leaves together by applying pressure to them upon their faces in the region of their edges.

5. In a spring the combination with a pile of leaves, of a rigid band surrounding the same; a plate interposed between the outermost leaf of the pile and the band and having guideways adjacent to the respective edges of the said leaf; and wedges in such guideways to clamp the said pile of leaves together by applying pressure to them upon the respective sides'of the longitudinal median line.

-6. Means to bind the leaves of a spring comprising a band to surround the leaves, a plate having separated guideways and adapted for interposition between the leaves and the band, and wedges adapted to traverse the guideways.

7. Means to bind the leaves of a spring comprising a band to surround the leaves, a plate having separated inclined guideways and adapted for interposition between the leaves and the band, stop-faces to hold it in position, and wedges adapted to traverse the guideways and for interposition between such plate and the band.

8. In a spring the combination with a pile of plates, of a rigid band surrounding the same, a member having a pair of guideways interposed between the pile and the band and wedges in said guideways.

9. A spring embodying a number of leaves assembled one upon the other flatwise, a pair of Wedges, and an abutment common to both wedges; the wedges being respectively active upon the edges of the flat face of the outermost leaf and the abutment.

10. A spring embodying a number of leaves assembled one upon the other flatwise,an abutment, a pair of wedges respectively active upon the edges of the flat face of the outermost leaf and upon said abutment which is common to both wedges, and means to maintain said wedges adjacent to the respective edges of such face.

11. In a spring the combination with a pile of leaves, of a rigid band surrounding the same and having greater inside height than the height of said pile of leaves, and clamping means interposed therebetween and reacting on the band and upon the said pile adjacent to its respective edges.

12. In a spring the combination with a pile of leaves, of a rigid band surrounding the same; a plate between the outermost leaf of the pile and said band and having reactionfaces adjacent to the respective edges of said leaf and directed toward the band; and wedging (rineans between said reaction-faces and the ban 13. In a spring the combination with a pile of leaves, of a band surrounding the same; a plate upon the pile of leaves; and wedging means interposed between the plate and the band and disposed parallel with the leaves, and the plate occupying a position between the leaves and said wedging means.

14. In a spring the combination with a pile of leaves, of a band surrounding the same, and wedging means interposed between the pile of leaves and said band having its line of movement parallel with the length of the leaves.

15. In a spring the combination with a pile of plates constituting the leaves of the spring, of a band surrounding the pile and having a portion engaging the plate at one end of the pile, portions engaging the edges of the plates at the respective sides of the pile, and a portion adjacent to but out of contact with the plate at the other end of the pile; and clamping means interposed between such plate and the said portion of the band.

16. In a spring the combination with a pile of plates constituting the leaves of the spring, of a band surrounding the pile and having a portion engaging the plates at one end of the pile, portions engaging the edges of the plates at the respective sides of the pile, and a portion adjacent to but out of contact with the plate at the other end of the pile; and compression means interposed between the edges of such plate and the said portion of the band.

Signed at Nos. 9 to 15 Murray street, New

York, N. Y., this 5th day of March, 1904..

STEPHEN W. BALDWVIN. 

